g-ilfillan



2 SheetsSheet 1.

(No Model.)

W. GILFILLAN. PNEUMATIC DOOR CHECK.

No. 311,742. Patented Feb. 3, 1885.

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2 Sheets -Sheet 2.

(No Model.)

W. GILFILLAN. PNEUMATIC DOOR CHECK.

Patented Feb. 3,1885.

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invite States Patent rricn,

WILLIAM GILFILLAN, OF NEW HAVEN, CONNECTICUT, ASSlGNOR TO SAR- GENT CO., OF SAME PLACE.

PNEUMATIC DOOR-CHECK.

SPECIFICATION fer-min part of Letters Patent No. 311,742, dated February 3, 1885.

\p; lication filed September 1, 18%. (No model.)

To aZZ whom it may concern;

Be it known that I, WVM. GILFILLAN, of New Haven, in thecounty of New Haven and State of Connecticut, have invented a new Improvement in DoonChecks; and I do hereby declare the following, when taken in connection with accompanying drawings and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this specification, and represent, in-

Figure 1, a view looking up toward the lin tel of the door, showing the check as applied, the door in the closed position, broken lines indicating the first part of the opening move ment; Fig. 2, the same as Fig. 1, the door open; Fig. 3, a longitudinal sectional view,enlarged; Fig. 4, an outside view of the disk G; Fig. 5. an inside View of the disk H of the piston: Figs. 6 and 7, modifications of the valve devices.

This invention relates to a device having for its object to prevent the slamming of a door when forcibly closed, and usually employed in connection with a spring.

Various devices to check the closing door P have been made, and in which a cylinder is employed, with a piston movable in the cylinder, to compress air therein as the door is closed. The air gradually escaping serves as a cushion to prevent the sudden closing or slamming of the door. Such checks are usually constructed so that they require to be applied near the hinge of the door. The momentum of the door in closing under the action of a spring is very great. The check being {1P4 plied near the hinge,the door under such momentum acts as a lever upon the hinge, the check being thefulerum, and so near the hinge that the power of the closing door upon the hinge is very great, and frequently breaks the hinge, or soon loosens the screws so as to derange the working of the hinge, and to such an extent is this diificnlty experienced that checks, otherwise satisfactory in their work, are di pensed with asadetriment, rather than advantage.

The object of my invention is the construction of a check which may be applied at any point within the range of the swinging door, and so far from the hinge that the strain upon the hinge heretofore experienced is avoided; and the invention consists, principally, in a cylinder open at one end combined with a piston and red, the one-say the cylinder-- stationary, the othersay the piston and rod applied to the door, and so that in op ning the door the piston is drawn entirely from the cylinder and held in position to enter the cylinder as the door approaches its closed position, and as more fully hereinafter described.

A represents the cylinder, in size corresponding to the door to which it is to be applied. It is simply a straight cylinder, provided with ears B or other devices by which it may be secured. The one end, C, is open. and made flaring to form the mouth or entrance to the cylinder. At the other end a cap, D, is applied. preferably, so as to screw onto that end of the cylinder, and upon its inside it should be provided with a packing, E, say, a disk of leather, which may abut against the end of the cylinder. At one or more points in the outer surface of the cylinder a groove, a,

is made, extending beyond the edge of the cap D, and turned into the cylinder as at b, forming a passage from the inside of the cylinder'ontward. As the cap is screwed onto the cylinder to a greater extent the packing will be compressed, and correspondingly reduce the aperture b, or, loosened, will correspondingly extend that aperture by the cap 1). Therefore the aperture 0 is made adjustable as to extent. Within the cylinder a pistonis arranged upon the end of a rod. F. The piston is best made as seen in Fig. 3, and consists of a disk, G, slightly smaller than the internal diameter of the cylinder, and a second cup-shaped disk, H, between which a packing l is arranged, this packing, as here represented, consisting of, say, a cup-shaped leather or other flexible material arranged between the disk G and the disk H, (shown in solid black in Fig. 3,) and so as to fit closely the interior of the cylinder, the cup shape inward or toward the closed end. On the piston is a collar, L, and between the collar L and the disk G is an elastic collar, M. On the face of the disk G next the elastic collar M one or more radial grooves, d, are made, leadin g to the center, and through the center around the piston corresponding longitudinal grooves, c, are made, as seen in Fig. 4, which form a passage between the collar M and the disk G, thence through the disk G. Through the disk H longitudinal openings f are made, leading into radial grooves h on the inner side of the disk H, as seen in Fig. 5. Onto the end of the piston a nut, N, is applied, which secures the piston to the rod. Thus constructed a passage is open betweenthe collar M from the open end of the cylinder through the piston to the other or closed end of the cylinder.

P is the bracket, to which the outer end of the piston-rod is hinged, as at 6. On the piston-rod is an arm, R,eXtending to one side of the pivot, and there provided with a spring, S, the tendency of which is to turn the arm from the bracket and correspondingly turn the piston-rod. From the opposite side of the piston-rod a similar arm, T, extends, and is provided with a set-screw, U,which may take a bearing on the bracket and limit the extent of movement to which the spring may turn the piston-rod.

In illustrating the operation of my invention I show the piston-rod as attached to the door and the cylinder to the lintel, and about midway the width of the door or little nearer the free edge of the door than the hinge, Z representing the door, at the hinge, and n the lintel. The, cylinder and bracket are arranged, as seen in Fig. 1, so that the axis of the cylinder and piston are at substantially right angles to the door when the door is in its closed position. Thus attached the door is opened until the piston just escapes from the end of the cylinder; then the set-screw U is turned until it comes to a bearing on the bracket, as indicated in broken lines, Fig. 1. The spring S, when the piston is free, holds it in the position of the set-screw, bearing against the bracket. Therefore as the door continues its opening movement, as seen in Fig. 2, the piston retains its same relative position to the door, and swings with it away from and independent of the cylinder. As the door is closed the piston approaches the cylinder in substantially a direct line, as indicated in broken lines, Fig. 1, and in the position to properly enter the cylinder, the flaring mouth ofthe cylinder making the en trance easy. Thus the piston moves out of the cylinder in opening the door, and into it in closing the door. If the door be forcibly closed, as under the influence of a spring, or a force of any character, the piston entering the cylindercushions upon the air therein,the said cushion forming a resistance to the advance of the piston and causing the piston to lie against the elastic collar M. That collar under such compression enters the passage (1 and closes it to prevent the escape of air within the cylinder outward through the piston. The air in the cylinder under the pressure of the piston is forced through the aperture 12 at the closed end, and that being small, the escape is so slow that the inward movement of the piston is retarded, and accordingly retards the final closing of the door, that final closing i being only permitted as the air escapes through the aperture 1). As before described, the aperture b may be adjusted to belarger or smaller. If larger, the air will sooner escape and permit the door to more quickly close. If it be smaller, the air will escape slower, and the closing of the door correspondingly retarded. As the door is opened air may enter through the same aperture 1) to supply the cylinder; but were no other provision made there would be substantially the same resistance to the withdrawal of the piston as to its entering; hence the first opening of the door would be resisted. To avoid this resistance, and make the opening of the door perfectly free, openings through the piston from the open .end. of the cylinder are provided. movement of the door commences, the pistonrod starts first from the piston, owing to the elasticity of the collar M, thereby opening the passage (1, which was closed when the piston entered, so that air may freely pass from the open end of the cylinder through the piston and to the opposite end of the cylinder to supply air to the cylinder as the piston retreats. This supply is sufficient to permit the piston to be freely withdrawn from the cylinder, and so as to offer substantially no resistance to the opening of the door.

The construction of the check so as to permit the entire withdrawal of the piston from the cylinder and its due return thereto enables the check to be applied at any point between the free edge of the door and the hinge, and so far from the hinge that the sudden arrest of the closing door by the check produces no strain upon the hinge, and thereby overcomes a serious difficulty existing in this class of checks constructed so as to be applied only near thehinge.

While I prefer to provide a supply of air to the'cylinder for the withdrawal of the piston other than that which would naturally flow inward through the aperture 1), such extra supply of air is not essential to my invention, as the simple aperture 1) may be sufficient; but in such case there will be some resistance to the first part of the opening of the door.

Instead of making the inlet for the air through the piston, it may be made in the form of a valve in the closed end of the cylinder, as seen in Fig. 6, the valve closing as the piston enters and opening as the piston withdraws, substantially as does the valve of a pump; or the inlet may be a simple valve upon the inner side of the piston, as seen in Fig. 7, which will open as the piston withdraws from and close as the piston enters the cylinder. The cup-shaped packing I permits the air to enter upon the inside of its flange, so as to force the packing against the cylinder as the piston enters, and the flange will contract as the piston retreats. This cup-shaped As the opening packing is, however, a well-known arrangement of packing for pistons, and while a good result is for atime attained in the employment of this packing, relying upon the compressed air to force the sides of the cup against the cylinder, after a little use the rim of the packing is liable to become so stilt as not to readily yield under the first impulse of com pressed air; hence a portion of the air in the cylinder will be permitted to escape around the piston before the sides of the cup come to a bearing.

To insure the expansion of the sides of the cup, I arrange a ring-shaped spring, a, between the inner surface of the packing and the periphery of the collar H, and as seen in Figs. 3 and 5. This may be simply a divided ring, as seen in Fig. 5, or made in several pieces, in the usual manner of piston-springs. It expands against the inner surface of the flange or sidesof the packing I sufficient to hold the outer surface of the packing I against the inner surface of the cylinder.

WVhile I prefer to arrange the stopping device for the piston as by a spring, S, and the adjusting-screw U, the stop may be inadjustable and, say, consist simply of the arm T, dispensing with the arm 1%, the spring S, and the adjusting-screw U, and so that the piston will be stopped or prevented from turning upon its hinge at the instant it passes from the cylinder, the arm being arranged with relation to the bracket so as to come to a hearing thereon when thisposition isreached; but in that case care must be exercised in applying the check to see that the bracket and cylinder are so attached in their respective positions that the piston will be stopped as it passes from the cylinder in the opening of the door, and remain in that position until the door is closed, and so that the piston may surely return to the cylinder.

The aperture b, instead of being made directly in the cylinder, may be made through the cap on the end of the cylinder, as indi-. cated in broken lines, Fig. 3; or it may be otherwise arranged, it only being essential that there shall be asmall aperture from which the air in the cylinder compressed by the piston passing into the cylinder may slowly escape. Under this construction of check,'which permits the piston to be drawn entirely from the cylinder, and consequently the arrange ment of the check at a considerable distance from the hinge, the cylinder may be made very much smaller than the usual arrangement, where the check is applied near the hinge, and which on heavy doors makes the check anything but an ornamental attach ment;

In applying the check,and in order to insure the proper relation of the bracket to the cylinder, I applya wood disk, J, (see Fig. 6,) to the pistourod at the mouth of the cylinder, and so that the piston standing at the inner end of the cylinder, the disk J forms a support for the piston at the other end, to hold it in its concentric position, and which position locates the bracket in its proper position for attachment with relation to the cylinder. With the two parts in that condition they are secured in their place. say, as seen in Fig. l,then the door opened. The withdrawal of the piston from the cylinder will take with itthe disk J. This disk, being of wood or other easily-destruct1- ble material, is readily removed from the rod, it having served its purpose as a guide or holder for the parts in their attachment.

I claim Y 1. The combination of a cylinder, open at one end, closed at the other except as to a slight aperture, a piston arranged to work in said cylinder, and a bracket to which said pistonrod is hinged, said braek et and cylinder being constructed the one for attachment to the door and to swing with the door,the other constructed for stationary attachment, and so that the two may entirely separate,the piston provided with a stop to arrest its turning upon the hinge on the bracket as it leaves the cylinder, sub stantially as described.

2. The combination of the cylinder A. open at one end, the cap D, adjustable upon the opposite end, the said cylinder constructed with an aperture, b, beneath said cap, and which is adjustable by said cap, a piston in said cylinder, the bracket P, to which the piston-rod is hinged, the said bracket and cylinder, the one constructed for attachment to the door and the other for stationary attachment, and so that the two may entirely separate upon the opening of the door, and a stop to support said piston as it leaves the cylinder, substantially as described.

3. The combination of the cylinder A, open at one end, closed at the other except as to a small aperture, a piston in the cylinder, the bracket to which the piston-rod is hinged, said bracket and cylinder constructed the one for attachment to the door, the other for stationary attachment, and separating the one from the other in opening of the door, said piston constructed with an aperture from the open end of the cylinder to the reverse side of the piston, a valve arranged to close said aperture in the piston, and a stop to hold said piston as it leaves the cylinder, substantially as described.

4. The combination of the cylinder A, open at one end, closed at the opposite end except as to a small aperture, a piston in the cylinder, the bracket P, to which said piston is hinged, said bracket and cylinder constructed the one for attachment to the door, the other for stationary attachment, an adjustable stop, by which said piston is held as it passes from the cylinder, and a spring arranged to turn the piston toward and hold it upon said stop, substantially as described.

5. The combination of the cylinder A, constructed open at one end and closed at the opposite end except as to a small aperture, the bracket P, said bracket and cylinder con- IOO strncted the one for attachment to the door, I

I and the inner surface of said packing I, sul)- between the periphery of the said collar H 20 the other for stationary attachment, a piston within the cylinder, its rodhinged to said bracket, said piston consisting of the disks G H and packing I, the said disks constructed stantially as described.

7. The combination of a cylinder, open at one end, closed at the other except as to a with an aperture through them from theopen slight aperture, a piston arranged to work in 25 side of the cylinder to the reverse side of the said cylinder, a bracket to which said pistonpiston, the elastic collar M, and fixed collar rod ishinged. said bracket and cylinder be- L on the piston-rod, substantially as and for ing constructed the one for attachment to the the purpose described. door and to swing with the door, the other 6. The combination of the cylinder A, conconstructed for stationary attachment, and so 30 structed open at one end and closed at the t opposite end except as to a small aperture, a bracket, 1?, said bracket and cylinder constructed the one for attachment to the door, the other for stationary attachment, a piston within the cylinder, its rod hinged to said bracket, said piston consisting of the disks G I H, cup-shaped packing I, and the spring 1?, L

that the two may entirely separate, with the removable disk J, arranged upon the pistonrod, substantially as described.

WVILLIAM GILFILLAN.

Witnesses:

ELLIOTT LITrLEJonN, CHAS. L. BALDWIN. 

